An over- glazed extension is an extension with substantial amounts of glazing – where the amount of glass exceeds 25% of the floor area – these are sometimes refered to as orangeries . In this case the extension, sun room or orangery is no longer compliant on an individual element basis. However the extension can pass L1B regulations using one of the alternative methods. In these cases building control ask for SAP calculations to prove compliance.
We will need a full set of plans for your extension and your existing property to carry out our calculations. Plans must be to scale and include all floor plans, Elevations, sections. We accept Autocad, PDF & hard copy plans. If you are unsure what is required please contact our technical department for details.